/*
 * Copyright (c) 2008-2016 Haulmont.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.haulmont.cuba.core.entity;

import com.haulmont.chile.core.annotations.MetaClass;
import com.haulmont.cuba.core.entity.annotation.UnavailableInSecurityConstraints;

import javax.persistence.MappedSuperclass;
import javax.persistence.Transient;

/**
 * Base class for persistent entities with identifier generated by the database on insert.
 */
@MappedSuperclass
@MetaClass(name = "sys$BaseDbGeneratedIdEntity")
@UnavailableInSecurityConstraints
public abstract class BaseDbGeneratedIdEntity<K extends Number> extends BaseGenericIdEntity<IdProxy<K>> {

    @Transient
    protected IdProxy<K> idProxy;

    @Override
    public IdProxy<K> getId() {
        if (idProxy == null) {
            idProxy = new IdProxy<>(this);
        }
        // return a copy cleaned from the reference to the entity
        return idProxy.copy();
    }

    @Override
    public void setId(IdProxy<K> idProxy) {
        this.idProxy = idProxy.copy(false);
        setDbGeneratedId(this.idProxy.get());
        this.idProxy.setEntity(this);
    }

    protected abstract void setDbGeneratedId(K dbId);

    protected abstract K getDbGeneratedId();

    @SuppressWarnings("unchecked")
    @Override
    protected void copySystemState(BaseGenericIdEntity src) {
        super.copySystemState(src);
        if (src instanceof BaseDbGeneratedIdEntity) {
            setDbGeneratedId((K) ((BaseDbGeneratedIdEntity) src).getDbGeneratedId());
        }
    }
}
